Every time you will know about the root cause for a bad habit you will get shocked because sadly addiction in many cases only reflect our weaknesses, lack of coping abilities and failure to handle stress correctly.
Addiction in many cases is a declaration of defeat. Some people get indulged into a bad habit after they feel that they were defeated. A man who had a goal of being famous then failed to do it might turn into a heavy drinker when he gets old.
Drinking is this case is a declaration of defeat and an unconscious message that says that his dreams werent possible.
Lots of those who had dreams and failed to reach them develop some kind of a bad habit. Some of them develop binge eating other develop chronic anger and keep shouting at everyone they meet while a third group become heavy drinkers.
In such a case the main reason those people cant quit the bad habit is that they dont have a drive or a motive to do it. Usually we try to quit a bad habit when it violates one of our violates or threatens our life in some way but if hope in life was already lost then why would we care?
If everything has collapsed already then why should we quit anything? And why should we care about our health or social life?
In such a case breaking the bad habit requires only one thing, reviving the hope, even if you were above 70 you can still revive the hope and try again. After all youd better die trying than die while you are declaring defeat.
Each one of us has many fields in his life that concerns him for example a normal person might be concerned about his career, his social life, his health and his hobbies.
When one of the major fields collapse it usually results in loss of hope that is transferred to all other fields. For example a girl who used to care about her body image might start binging when she breaks up.
In this case the relationships field collapsed and the loss of hope was transferred to her body image field. Again not caring about her body image is a declaration of defeat that resulted from the loss of hope she experienced.
If this is the underlying cause for your bad habits then know that unless you restore hope to your life you wont be able to quit the habit.